public class MyCycleQueue2 {
    public int[] elem;
    public int usedSize;

    public int front;
    public int rear;

    public MyCycleQueue2(int k) {
        elem = new int[k+ 1];
    }

    //入队列
    public boolean enQueue(int value) {
        if(isFull()){
            return false;
        }
        elem[rear] = value;
//        rear++;
        rear = (rear + 1)% elem.length;
        usedSize++;
        return true;
    }

    //出队列
    public boolean deQueue() {
        if(isEmpty()){
            return false;
        }
//        front++;
        front = (front + 1)% elem.length;
        usedSize--;
        return true;
    }

    //获取队头元素
    public int Front() {
        if(isEmpty()){
            return -1;
        }
        return elem[front];
    }

    //获取队尾元素
    public int Rear() {
        if(isEmpty()){
            return -1;
        }
        int index = (rear == 0) ? elem.length - 1 : rear - 1;
        return index;
    }

    public boolean isEmpty() {
        return usedSize == 0;
//        return rear == front;
    }

    public boolean isFull() {
        return usedSize == elem.length;
//        return (rear + 1)%elem.length == front;
    }
}
